ok here's the deal, has anyone thought about running a relay jumping the fuse on the abs/traction control? i mean in theory with the flip of a switch you could either disable the system or turn it right back on without removing the fuse or having to make the choice between abs or none all the time. just though i would throw that out there.

 

From my recent experience with popping the fuse on the dyno, you will disable the ESP/TC but get a 5,000 RPM rev limit and a raised spoiler.

 

Hey woody, have you ever popped the TC/ESP fuse and driven on the road this way? Will disabling the TC for on road use reduce my Redline limit and deploy the wing at speeds under 55 mph?

 

I have whilst trying to figure out the dyno issues (F17 and F18 I think) and I did get the 5,000 rpm limit, but I was also messing with the wheel sensors too. I think HDDP runs with the system completely disabled by pulling the fuse and doesn't have a problem with the rev limit, but he has a completely gutted car with all sorts of other systems removed/unplugged too.

 

Actually Woody, that raises a good question. I only pulled the fuses for the dyno to bypass the TC that was causing problems. I have never run the car on the track with the fuses removed, I'm wondering if I would get a rev limit at 5,000 ? The TC still kicks-in VERY late when I get a bit on the squirrelly side. I have yet to disable it completely because I still like to use the ABS so I don't flat spot my tires going deep into the turns.

Although, you are correct that most of my non-essential wiring has been removed which has thrown a BAS/ESP light on what's left of my console.

Perhaps the next time I run the car, I'll pull the fuses to see if I notice any changes in the TC activation, RPM limit, or ABS.

 

I am unable to find that darn fuse, isn't it located next to the relay control module or do I have to slide the relay box out of the compartment to access F18? I see about half a dozen blue 15 amp fuses that are only numbered 1 thru 10 next to the big orange fuse.

I guess I'll have to study that wiring schematics again...

 

Would you like me to take a photo of the fuses for you ?

 

Yes please if it's not too much trouble. By the way I did a search and found this post, is this correct guys???

USE THESE INSTRUCTIONS AT YOUR OWN RISK. FOLLOWING THESE INSTRUCTIONS MAY RESULT IN AN UNSAFE CONDITION AND MAY VOID YOUR WARRANTY.

1. Locate the Engine Fuse Block. It is located to the right rear of the engine compartment in front of the battery.
2. Open the Engine Fuse Block Cover and locate the ABS System fuse. It is the #3 Fuse. It is the MIDDLE fuse and cable between the 2 black cables. It is a 50 Amp fuse.
3. Using an 8mm socket remove the nut holding the ABS System CABLE. It is the one that does NOT have the long silver bar under it.
4. Remove the cable from the bolt. COMPLETELY wrap any exposed metal on the cable in electrical tape.
5. CAREFULLY bend the cable back on itself and tape the now wrapped end connector to it's own cable or an adjacent cable.
6. Put the nut back on the bolt and tighten it up you might want to use a little loc-tite to keep it from rattling loose.
7. Close the Engine Fuse Block Cover.
8. Close the hood and drive the car.

Disabling the ABS System in this way WILL illuminate the Amber ABS System Warning Indicator Lamp and the Amber Brake Assist Warning Lamp located on the bottom right side of the Instrument Cluster.
There is no fuse to disable these lamps. You will need to remove the lamps from the Instrument Cluster to disable them.
see attached pdf's for pictures.

USE THESE INSTRUCTIONS AT YOUR OWN RISK. FOLLOWING THESE INSTRUCTIONS MAY RESULT IN AN UNSAFE CONDITION AND MAY VOID YOUR WARRANTY.
I DO NOT RECOMMEND DISABLING THE ABS SYSTEM.

 

I don't know where you got that info but it's interesting. Where did you find that ?

 

Here's how to disable the TC for a dyno run, but still be plagued with a 5k rev limit. I'll have to do some tests to see if the 5k rev limit will persist otherwise. Or perhaps Woody has already tested it and has a work around.

 

I found the ABS/ESP/TC disconnect here: https://www.crossfireforum.org/forum...highlight=fuse

Thanks for the pix, will have to try both and see what happens.

 

LOL... Perhaps you found something that we all overlooked...

 

Just an update on this:

After speaking with Derek this morning I have discovered that the Euro and US cars have the main fuse box in different locations; mine is in the engine compartment and the US cars have it in the end of the dash, where mine has a smaller auxiliary fuse panel. As a test on my way in to work I popped F17 and F18 (marked as ESP) and set off. I got the ESP/BAS and ABS warning lamps on but not the spoiler deployment/5,000 RPM limit. So it looks like you should be OK disabling the system this way. The roads were too busy for me to try and sideways motoring to see how 'disabled' the system actually is in this state. However, I know from my dyno tests that even with the fuses pulled the ECU still checks the speed sensors and throws a fault if you disconnect them. From my recollection of the schematics the F3 fuse that Derek pulled actually feeds F17/18 anyway so I think we are basically doing the same thing. I will check tonight on my drive home if there is a difference between F17 and F18 (as stated the legend labels them both as ESP) i.e. can you disable the TC/ESP but leave the ABS functional.

 

So the front wheel speed sensors are the key to the good dyno run...? Would it not be fairly easy to wire the sensors in parallel with the rear wheel sensors (and using a resistor) to simulate all 4 wheels turning the same speed. This would get you a good dyno run over 5,000 rpm?

 

You have probably missed some of the earlier dialogue on this. I have been looking at this over the last few weeks and that was my initial thought too. But as ever it is not quite that simple. The sensors are actually quite sophisticated current rather than voltage output devices, so simply wiring them in parallel does not work; the ECU performs a constant test on the sensor signals which impart speed, direction and gap data via variable width current pulses. I have now got a 'breadboard system to take the rear wheel signals an output corresponding front wheel signals. The next step is to hook it all up on the car. Here's more details on my site:
Dyno mods

 

I believe on my SLK320, I have a switch which turns off the TC, and does not limit RPMs. Not sure how it is wired in...have no engine manual. Will check with my SLK buddies to see if they have any info.

 

Yep, the xfire switch doesn't limit RPM either, it was only doing this whilst messing with the speed sensors and TC/ESP fuses at the same time.